This guide will let you know how to unlock the Crash Town Kalin Kessler in Duel Links.
First, you will need to collect the harmonicas by collecting the 114 dueling in the game.
You can get these by dueling standard duelists, legendary duelists, and playing the ranked matches. As you can see, there are three characters; the first one has a yellow background color and the second one has a blue background in color, and the last one has a grey background, as shown in the image below.
The character with a grey background will give you four spaces if you can beat him. The blue background turbo character will give you six spaces and put you at Sr Joule. The last character, which has a yellow background color, will double into twelve.